The shift informed all aspects of the design. Here, sketches of patterns that the designers then tried to produce using CNC milling.Photos: Alex Washburn / WIRED

The new size was made possible by a shift from machine stamping to CNC milling. It allows the Mini to save precious space. The first Jambox (here on the left), required, say, 3 millimeters for the plastic box, one millimeter for space around that, another millimeter for the metal skin. With this one (on the right) "that 1.1 or 1.2 millimeter wall thickness is all you’ve got," explains designer Yves Behar. Photo: Alex Washburn / WIRED

Since machine time is costly, the designers had to figure out how to make the speaker's signature patterns and textures as quickly as possible. Photo: Alex Washburn / WIRED

A bottom-view of the pinch-foot that was eventually discarded (but patent-protected). Photos: Alex Washburn / WIRED

The result is a sharper, sturdier-feeling speaker. And one that can slip into any decent-sized pocket. Photo: Alex Washburn / WIRED

“Putting a seal with the right amount of pressure on the inside of what essentially is your outside..." says Behar. "That’s hard to do." Photo: Alex Washburn / WIRED

Mini Jamboxes. Photo: Alex Washburn / WIRED

Mini Jamboxes. Photo: Alex Washburn / WIRED

Jawbone’s first wireless speaker was something of a rarity when it was released at the end of 2010. At a point when so many of our favorite gizmos were being subsumed by our smartphones, the Jambox was, quite simply, a standalone survivor. It did something novel–music! wirelessly!–it did it well, and it did it all in an attractive, I-wanna-play-with-one-of-those-things package, courtesy of designer Yves Behar.

And while some of its competitors have since bested its audio quality, it has always retained an undeniable cool factor, and thus a good deal of visibility in the increasingly crowded category. Last year, Jawbone expanded the line with the dance party-ready Big Jambox. Now comes the Mini Jambox, which takes advantage of an all-new manufacturing approach to retain some of the cool factor of the original, and then some.

The Mini Jambox, available for preorder today at $179, is a slimmer, sharper version of the original. Gone is the rubber that capped the top and bottom; the new device is cool metal all the way around. In terms of first impressions, it might seem slightly less friendly than the first Jambox, but it proves no less touchable. And, once you get your hands on it, it exudes superior quality–not unlike the difference between the iPhone 3GS and the iPhone 4 that followed it.

“This is a complete reinvention of everything we’ve done in the past, for the purpose of sound and size.”

Of course, the Mini Jambox makes good on its name: It’s nearly half the size of the original Jambox by volume. And while it doesn’t necessarily look mini, it does feel mini, and when you’re talking about something that’s supposed to go in a pocket as much as a purse or a backpack, that’s important. Behar and Hosain Rahman, Jawbone’s CEO, were determined to bring it in at under an inch of thickness–it ended up a millimeter or two under–and while there may not be room for it in your skinny jeans, you could certainly slip one in a jacket, or a hoody’s pouch.

The biggest departure, though, is in the way the Mini Jambox is manufactured. The original Jambox was basically built like any other speaker: The drivers, passive resistor, Bluetooth antenna, and all the other guts were housed in a sealed plastic enclosure, a package that was then in a thin piece of metal, stamped with industrial-grade presses to lend the speaker its beloved texture. Creating that internal seal is essential for good sound, but in the case of the first Jambox, that outer, stamped piece was largely cosmetic–the Jambox Remix, introduced last year, gave users the chance to swap in differently colored grills and end caps as they desired. In other words, the stuff going on inside the speaker was altogether separate from the stuff going on outside.

With the Mini Jambox, the outside is integral to the functioning of the inside. For the new version, Jawbone moved from stamping to CNC milling, allowing them to streamline the internal design of the speaker to a remarkable degree. The Mini’s body is a single piece of extruded, anodized aluminum which serves not only as the device’s outer shell, but as the sealed box for the sound cavity inside, too. With the original Jambox, all the actual speaker business was held in place by a skeleton, with a skin wrapped around it. With the Mini Jambox, the skeleton and the skin are one in the same.

Opting for CNC instead of stamped metal might not seem like a big deal, but it informs the Mini’s design through and through. As Behar explains it, “This is a complete reinvention of everything we’ve done in the past, for the purpose of sound and size.” In terms of size, the unibody design allowed Jambox to eliminate several layers of stuff inside the speaker, making for greater internal volume–and thus better and louder sound–in a package that’s half the overall size. It’s the same idea behind the celebrated unibody design of the Macbook Air. Where the design for the original Jambox demanded several layers–maybe 3 millimeters for the plastic box, one millimeter for space around that, another millimeter for the metal skin–with the Mini, Behar says, “that 1.1 or 1.2 millimeter wall thickness is all you’ve got.”

The approach came with its challenges. “There’s a lot of innovation around how you essentially put this not in a sealed box, but rather have all of this seal itself,” Behar says. For one, it necessitated a switch to the aluminum body–a material whose rigidity made that tight seal possible (and ultimately allowed the engineers to better fine-tune the sound the Mini was producing.)

The switch to CNC informed the design through and through.

But the milling also presented a challenge in terms of the patterns that decorate the front and back of the speaker. Compared to stamping, CNC work is pricey, so Jawbone and Behar had the unique challenge of figuring out what sort of patterns they could make using as little machine time as possible. Some early ones took upwards of a hundred minutes under the drill. But by working out the unique geometries possible with a gigantic, robot-controlled drill bit–how intersecting imprints and fast sweeps of large, circular bit, for example, could result in diamonds or other angular patterns–Jawbone got the high-tech choreography down pat, with the final textures taking just about two minutes of machine time on average. “These are actually made with single bits, extremely fast,” Behar says, examining one variety of the Mini’s fine metal grills. “But you’d never be able to tell.”

After all the experimenting, Jawbone settled on five different patterns (and nine colors) for the final product. Getting those right was key. “Color and textures have always been a way that we take these technological products and make them human and personal–to allow people to have opinions, to like something or not like something,” Behar says. “A very different philosophy from other design-leading companies out there.”

The original sketches for the Mini from Behar’s personal notebook. Photo: Alex Washburn / WIRED

Arriving at that final product involved some dead ends along the way. For every texture the designers were able to execute in a cost-efficient way with CNC, there was another that was left in the sketchbook. More unusual form factors were ultimately dropped in favor of the simple box, and other features were phased out as the design took shape. At one point, a skinnier prototype sported a rubber foot that pinched open, offering some support for the tottering unit. The final design was thick enough to stand on its own, but the aluminum bottom introduced another problem: when the bass got pumping, the lightweight speaker would start to walk across the table, even with sizable rubber feet. The solution, interestingly, was to make the feet smaller. The less rubber they used, the designers found, the better the speaker clung in place; in the end, the Mini has just two small strips on either side of its bottom face.

The Mini, like its forebear, is still a speakerphone, though the omnidirectional mic has been moved to the side of the speaker for better coverage. It still includes Jawbone’s LiveAudio DSP tech. But there are a few new updates to the package. To keep bass in the mix, the Mini borrows a clever trick from the Big Jambox; as you turn the volume down, the bass isn’t lowered as much as the rest of the track, so you can still hear bass lines and kick drums even at lower decibel levels. Another new bit is the Jambox app–a smartphone application that slurps down playlists from disparate music services–iTunes, Spotify, Rdio, etc–and gives you access to all of them in one bubbly interface. The app lets you control the Jambox, too, reassigning its hardware buttons and changing the device’s computerized voice.

As Behar explains it, the design of the Jambox Mini was one driven by process. “Part of designing this,” he says, “was asking ourselves, ‘What’s the next method that we can develop that’s going to give us as much volume as possible.'” Of course, when he says this, he’s talking about the space inside the unit–not the decibels you’ll be able to crank out of it. Which gets at the heart of what’s really interesting about the new Jambox, from a design perspective. While the Mini may indeed jack up the outward cool-factor of the original, the coolest stuff is all happening out of sight–underneath the swooping arm of a gigantic drill bit somewhere in China and packed tightly inside that cool unibody shell.